1. Field of the Invention
The present invention relates to a liquid crystal display device, in particular, a data-line driving circuit included in a liquid crystal display device.
2. Description of the Related Art
A liquid crystal display device includes a plurality of pixel circuits. A data-line driving circuit included in the liquid crystal display device feeds a potential for allowing each of the pixel circuits to display a grayscale through a data line. It takes a certain period of time for the potential actually fed to each pixel circuit to reach a potential output by the data-line driving circuit to the data line. The reasons for the time include a parasitic capacitance generated between the data line and another wiring, a delay due to a wiring resistance, and insufficient driving capability of transistors. Therefore, a difference is generated between the potential of the pixel circuit reaching within a horizontal period and the potential applied to the data line. For preventing deterioration of image quality due to the difference in potential, a potential obtained by correcting the potential indicating a display grayscale is fed to the data line so as to reduce a difference between the potential actually fed to the pixel circuit and the potential indicating the display grayscale in an existing technology.
Japanese Patent Application Laid-open No. 2008-209890 discloses a display device in which a potential obtained by correcting a potential indicating a display grayscale is fed to a data line.
In the case where the signal to be fed to the data line is corrected for changing the potential of the pixel circuit within a shorter period of time, the potential of the corrected signal is a potential emphasizing a difference between the potential to be fed to the pixel circuit in a preceding stage and the potential to be fed to the pixel circuit in the current stage with respect to pixel circuits which connects the same data line. When a conventional data-line driving circuit is used, however, the signal cannot be satisfactorily corrected in some cases. For example, the data-line driving circuit cannot feed a potential lower than a potential for the lowest-level grayscale. Therefore, when the display grayscale changes from the highest-level grayscale to the lowest-level grayscale, the potential cannot be corrected to be lowered any more. Thus, the difference between the potential that the pixel circuit should reach and the potential that the pixel circuit actually reaches within the horizontal period becomes larger. As a result, image quality is sometimes deteriorated.